BALTIMORE(WJZ) — New warnings about a deadly virus. Federal health officials are posting an advisory at the nation’s largest airports about the MERS virus. The deadly illness has no vaccine, no cure and kills about a third of those infected.

Meghan McCorkell has more on the latest warning.

More than 140 people have died of the MERS virus, mostly in the Middle East. Now the CDC is warning airline passengers here in the US to be aware.

Before taking flight at BWI, there’s a new health advisory for travelers. The CDC is warning passengers at 22 of the nation’s airports about Middle East Respiratory Syndrome, or MERS.

“These airports were picked because they cover most of the flights to and from the Kingdom of Saudi Arabia and the United Arab Emirates,” said Christine Pearson, CDC.

More than 500 cases of the deadly virus are reported worldwide, mostly in the Arabian Peninsula.

The World Health Organization stops short of calling it a public health emergency.

“It’s clear right now that we don’t see any evidence of community infections sweeping through,” said Dr. Keiji Fukuda, World Health Organization.

Two cases are confirmed in the US: one in Indiana and another in Florida. Both involve healthcare workers who traveled to Saudi Arabia.